Helena Bay slip: Work hauling 15,000 truckloads to start next week
Work to remove material from the Helena Bay hill slip will start next week but experts warn the area’s geography means it won’t be straightforward.
The massive 110,000cu m slip on Russell Rd came down after heavy rain saturated the region on January 21.
The road closure means about 800 households in the Helena Bay, Ōakura, Teal Bay and Whangaruru areas face a drive of at least 90 minutes to Whangārei, on a road so treacherous that pilot vehicles are running seven days a week to help guide drivers.
Non-residents are encouraged to access the area through the Ōpua car ferry, a trip that takes about two and a half hours.
Whangārei District Council has warned it will take until June to clear the slip material in 15,000 truckloads, then an unknown amount of time to fix the road under the slip.
Project lead Curt Martin from Censeo Consulting said preparation work has been underway, preparing a nearby site for cleanfill.
From next week, the site will be ready for contractors to start hauling out material from the slip, using large Moxy trucks that are commonly used in mines.
The 110,000cu m is about half the size of the slips that closed State Highway 1 at Brynderwyn Hills for four months in 2024, but it is concentrated in just one area and the geography is much more complex, Curt Martin said.
A previous under slip, which closed Helena Bay hill for four months in 2007, has shown some signs of movement, so smaller trucks will be used to safely travel over this site.
The slip itself is still moving and settling, so material will have to be taken out from the top first, with benching worked in down the hill face, he said.
Fortunately, the landowner of an old forestry block above the slip has given permission for their land to be used, Curt Martin said.
The site is not only crumbly greywacke material but also includes huge basalt boulders – many larger than a car – which will need to be picked out of the hill face, he said.
“We’re going to cut this batter back but the problem is it’s pock-marked with these boulders.
“If we find them, we will have to cut them out and that will slow the excavation.”
Curt Martin said it is not possible to simply push the slip material off the road and down the hill, as many people have suggested on social media.
For a start, it is not safe for contractors to work on the road yet as slip material from the top could come down on them, he said.
Pushing the material off the road could “throw havoc” on the river below, as well as damaging private property, and flora and fauna, Curt Martin said.
Hikurangi-Coastal ward councillor Stephen “Tractor” Martin said the impacted community are coping remarkably well with the isolation and inconvenience.
“I’m just so proud of the way people are conducting themselves – with the way things are at the moment, it’s a big challenge for a lot of people," Stephen Martin said.
“I think the biggest thing we can do is be patient.”
Denise Piper is a news reporter for the Northern Advocate, focusing on health and business. She has more than 20 years in journalism and is passionate about covering stories that make a difference.